Stress and the stress-reducing properties of alcohol are frequently implicated in the initiation of heavy alcohol consumption. Evidence for this hypothesis of alcoholism is still controversial. Recently, we could show in rats why perhaps controversial results were obtained and produce some biochemical evidence for a stress reducing effect of alcohol. Alcohol effects plasma and brain catecholamine levels differently in nonstressed vs. stressed rats; it can produce stress-like effects in nonstressed animals whereas it can reduce stress in stressed rats. Among stressed rats, we identified rats with "high" or "low" stress responses. Through selective breeding, we found in preliminary experiments that this stress response has a genetic component. We observed also that alcohol reduced the stress response only in certain animals and that the reducing response has a genetic component since we were able to breed in preliminary experiments rats selectively for a "low" or "high" alcohol reducing response. However, these experiments need verification and extension. Thus, we plan to study the effects of alcohol on plasma and brain catecholamines in nonstressed and stressed rats. We plan to selectively breed rats for their individual stress responses alone (catecholamines) as well as for their reducing responses to alcohol during stress. These studies will lead to different lines which are "high" or "low" stress responders or "high" or "low" alcholhol reducers. These animals will then be characterized chemically, tested behaviorally and subjected to voluntary alcohol intake during stress. These studies will be done in collaboration with other investigators with expertise in stress and/or alcohol research. This novel approach will supply definite biochemical, behavioral and genetic data on the interaction between alcohol and rats which will hopefully provide information on the pathogenesis(es) of alcoholism.